This invention relates to a process for producing flexible sheets or other shaped articles from vegetable particulate materials.
Japanese Laid Open Patent Application (Kokai) No. 106932/1984 discloses a process for producing sheets or other shaped articles of vegetable particulate materials bonded together with a binder resin by coating the particulates with isocyanate terminated urethane prepolymers or polyisocyanate compounds and then rolling or otherwise shaping the resultant mass under pressure. The urethane prepolymer or polyisocyanate compound applied to the particulates crosslinks individual particles together through a chemical reaction of the isocyanate group with atmospheric moisture or active sites possessed by the particles. This process requires relatively large amounts of binder prepolymer or compound and is not suited for mass production of inexpensive articles such as planter pots. Furthermore, relatively long curing time and blocking to the mold prevent the process from being applied to mass production of shaped articles on continuous basis.
The process of this invention is distinguished from the prior art in that it provides flexible sheets or articles in a cost effective manner.